8) The points (2,0,1), ( 3,2,-1) and ( 1,1,-3) form a) An isosceles triangle but not right angledb) An isosceles right angled trianglec) An equilateral triangled) None of these.

9) The points (4,1,0), (3,-1,2), (5,0,4) and (6,2,2 ) are given. Which
of the following is more correct?a) the points form the vertices of a parallelogramb) the points form the vertices of a rhombusc) the points form the vertices of a rectangled) the points form the vertices of a square.

10) The ratio in which the line segment joining the points ( 2,4,5)
and ( 3,5,-4) is divided by the yz-plane isa) 2:3 internalb) 3:4 internalc) 2:3 externald) 3:4 external

11) The angle between the lines 2x+3y+z-4=x+y-2z-3=0 and 5x+8y-7z
= 10x-2y-2z=0 isa)b)c)d) None of these

12) The point of intersection of the lines,
is

a) (2,1,-3)b) (1,-3,2)c) (-3,2,1)d) None of these

13) The shortest distance between the lines
is

a)b)c)d)

14) The equation of the plane passing through the points
( +2,6,-6), (+3,10,-9) and (+5,0,+6) isa) 10x+7y+6z-14=0b) 10x-7y-6z-14=0c) 10x-7y+6z+14=0d) None of these

15) The image of the point P(1,2,3) in the plane 2x+y+z-3=0
isa)b)c)d)

36) The image of the point
P (1,3,4) in the plane 2x-y+z+3=0 isa) (3,5,-2)b) (-3,5,2)c) (3,-5,2)d) (3,5,2)

37) The line,
intersects the curve
if c=a)b)c)d) None of these

38) A plane passes through
a fixed point ( a,b,c ) . the locus of the foot of the perpendicular to it from
the origin is a sphere of radiusa)b)c)d) None of these

39) The
shortest distance between the z-axis and the line, x+y+2z-3 = 0, 2x+3y+4z-4=
0a) 1b) 2c) 3d) none of these

40) The smallest radius of
the sphere passing through (1,0,0), (0,1,0) and (0,0,1) isa)b)c)d)

41) A parallelopiped
is formed by planes drawn through the points( 5,7,9) and (2,3,7) parallel
to co-ordinate planes. The length of an edge of this rectangular parallelopiped
isa) 2b) 3c) 4d) all the above